1. Field
The subject matter presented herein relates generally to imaging devices and methods, and more particularly, to an imaging system that uses a directed-energy device.
2. Description of Related Art
U.S. Pat. Nos. 7,098,662 and 7,061,241, for example, can be used as references to illustrate principles of known Magnetic Resonance Imaging (MRI) systems and their disclosures are incorporated herein by reference in their entirety.
In the static magnetic fields commonly used in known magnetic resonance imaging (MRI), the energy difference between the nuclear spin states can correspond to a photon at radio frequency (RF) wavelengths. Resonant absorption of energy by the protons due to an external oscillating magnetic field can occur at what is referred to as the Larmor frequency for the particular nucleus.
A practical value of this phenomenon resides in the signal emitted by the excited spins after an excitation signal is terminated. The emitted signal can be a function of at least one and typically several physical properties of the spin that generates the signal and therefore, by examining the emitted signal, the properties of the spin can be determined. If the region of interest of a target (human tissue), is subjected to a separate magnetic field which is in the x-y plane and which is near the Larmor frequency, the net aligned moment, or “longitudinal magnetization” may be rotated, or “tipped” to produce a net transverse magnetic moment. A signal can be emitted by the excited spins after the excitation signal is terminated. In known MRI systems, the emitted magnetic resonance signals can be acquired, digitized and processed to generate a magnetic resonance data set that can be used to produce an image of the target, typically a two dimensional cross section or slice.
Known MRI systems can typically includes a plurality of gradient coils positioned about a bore of a magnet to impress a polarizing magnetic field and an RF transceiver system with an RF switch controlled by a pulse module to transmit RF signals to an RF coil assembly, i.e., antenna, and to acquire the magnetic resonance signals emitted by the region of interest within the target.
As further background, the configuration and operation of directed energy devices varies widely as is illustrated by the disclosures within U.S. Pat. Nos. 6,809,307; 6,784,408; 6,849,841; 6,864,825 and 7,126,530, which are incorporated herein by reference in their entirety.